Of the following elements, which one would have the largest radius?

Question options:

Nitrogen (N, atomic #7)

Lithium (Li, atomic #3)

Neon (Ne, atomic #10)

Boron (B, atomic #5)

Your answer should be Lithium.

In general, there is a periodic trend that a n atom gets bigger as the number of electron shells increase, so the radius of an atom increases as you go down a certain group in the periodic table of elements and will decrease as you move from left to the right of a certain period. This is partly because of electron shielding. Note that periods are the rows and groups are the columns.

These elements are all in the same period. Going across the period left-to-right, atomic radius decreases. The leftmost element, which must have the highest radius, is Li.